Assuming that the steel pieces are 2 floors high or roughly 10 meter, 3 more jumps are needed to reach 300 meter

Each steel columns (core steel columns) is adding 9 meters to the tower. So it takes another 3 new sets of steel columns to breach 300m mark.
In the core part they are now working on 4 day cycle speed. So it takes another 24 days to reach the goal of 64fl.
All in all it is very possible to reach 300m provided the weather is as smooth as it is these days